listening-to-events.md

Listening to Events

When a class needs to receive input events, such as keypresses, it must implement the InputEventListener interface. Once registered in the InputManager, it will receive input events each time the user generates them.

{% plantuml %} interface InputEventListener { bool onKeyDown(const Key & k) bool onKeyUp(const Key & k) bool onWindowEvent(const WindowEvent & event) }

class MockInputEventListener { int getNumKeyDownPresses() int getNumKeyUpPresses() int getNumWindowEvents()

bool clear()

vector getStoredKeyUpPresses() vector getStoredKeyDownPresses() vector getStoredWindowEvents() } class Key class WindowEvent InputEventListener <|-- MockInputEventListener InputEventListener -- Key : receives InputEventListener -- WindowEvent : receives {% endplantuml %}

InputEventListener

This interface has the following functions, that are called when the corresponding event is triggered in the InputManager:

• onKeyDown(): called when a key is pressed, the event passed stores the key that triggered the event.
• onKeyUp(): called when a key is released, the event passed stores the key that triggered the event.
• onWindowEvent(): called when a window event happens, the event passed stores the event type and information.

MockInputEventListener

Implements the following functions to extract information about received input events:

• getNumKeyDownPresses(): returns the number of key down events received.
• getNumKeyUpPresses(): returns the number of key up events received.
• getNumWindowEvents(): returns the number of window events received.
• clear(): clears all events received.
• getStoredKeyUpPresses(): returns a vector of key down events received.
• getStoredKeyDownPresses(): returns a vector of key up events received.
• getStoredWindowEvents(): returns a vector of window events received.